Is PU foam sustainable?

PU foam: an environmentally-friendly insulation material.

When is an insulation material sustainable? If it is made of natural products? Or if it fulfils its insulation task reliably and for a long time? At the end of the day, climate protection is about how much energy an insulating material saves and therefore reduces the production of CO2. Thanks to its excellent insulation values, construction foam saves much more energy in a very short time than was needed for its own production. And all this with a life-span of more than 30 years.